#include<iostream>
using namespace std;
/*
常见的函数样式有4种
1、无参无返
2、有参无返
3、无参有返
4、有参有返
*/
//1
void test01(){
    cout<<"this is test01"<<endl;
}
//2
void test02(int a){
    cout<<"this is test02 a="<<a<<endl;
}
//3
int test03(){
    cout<<"this is test03"<<endl;
    return 1000;
}
//4
int test04(int a){
    cout<<"this is test04 a="<<a<<endl;
    return a;
}

int main(){
    //1
    test01();
    //2
    test02(100);
    //3
    int num1=test03();
    cout<<"num1="<<num1<<endl;
    //4
    int num2=test04(10000);
    cout<<"num2="<<num2<<endl;
    return 0;
}
